Butt welding pipe



Patented Dec. 17, 1935 UNITED STATES PATENT OFFICE 7 2,025,001 BUTTWELDING PIPE No Drawing. Original application February 10,

1934, Serial No. 710,756. Divided and this application November 20,1934, Serial No. 753,992

4 Claims.

This invention relates to the production of pipe by heating skelp in afurnace and then passing it through a welding bell, this being generallyknown to the trade as the butt-welding process, and is a division fromour co-pending application entitled Butt-welding pipe, bearing SerialNo. 710,756 and filed February 10, 1934. One of the objects is to applyoxidizing gases to the edges of the heated skelp in such manner that theskelp is not unduly burnt. Other objects may be inferred.

Our method of applying oxidizing gases to the edges of the skelpconsists in successively applying heated air and a mixture of heated airand oxygen to the edges of the skelp after leaving the furnace andbefore passage through the welding bell. The volume of the air should beconsiderably greater than that of the mixture of air and oxygen, and thelatter should be proportioned to contain from 20 to 65 per cent ofoxygen by volume.

The large volume of air provides for an initial combustion of any scaleor other substances on the edges of the heated skelp, whereby thetemperatures of these edges are raised somewhat 5 to raise thetemperature of the edges to the usually desired maximum. The proportionsof the heated air and oxygen contained in the smaller volume of themixture are advantageous because it has been found that this producesall the heat that is desired, without any undue burning.

We claim:

1. In the method of producing pipe by heating skelp in a furnace andthen passing it through a welding bell, the step consisting insuccessively applying heated air and a mixture of air and oxygen to theedges of the skelp after leaving the furnace and before passage throughthe welding bell.

2. In the method of producing pipe by heating skelp in a furnace andthen passing it through a welding bell, the step consisting insuccessively applying heated air and a mixture of air and oxygen to theedges of the skelp after leaving the furnace and before passage throughthe welding bell, the volume of the air being greater than that of themixture of air and oxygen.

3. In the method of producing pipe by heating skelp in a furnace andthen passing it through a welding bell, the step consisting insuccessively applying heated air and a mixture of air and oxygen to theedges of the skelp after leaving the furnace and before passage throughthe welding bell, said mixture being proportioned to contain from to percent of oxygen.

4. In the method of producing pipe by heating skelp in a furnace andthen passing it through a welding bell, the step consisting insuccessively applying heated air and a mixture of heated air and oxygento the edges of the skelp after leaving the furnace and before passagethrough the welding bell, the volume of the air being greater than thatof the mixture of air and. oxygen and the latter being proportioned tocontain from 20 to per cent of oxygen.

JAMES LESTER MAUTHE. WALTER T. MAHLA.

